Keyboard operated switching unit



April 16, 1963 A. M. PASINSKI ETAL KEYBOARD OPERATED SWITCHING UNIT .m 1w? t TSN e NNw W Y; W J D m MR 5 mm AR Filed Dec. 28, 1961 ATTORNEYApril 1963 A. M. PASINSKI ETAL 3,085,746

KEYBOARD OPERATED SWITCHING UNIT A E. wwnwwwwmguifi wwawww uwflwwmwwlwwmfi QAI 50 OAIOBI wwnwm' m m fim INVENTORS. ARTHUR M. PAS/NSKI,RICHARD J. JABLONSKI.

ATTORNEY April 1963 A. M. PASINSKI ETAL 3,085,746

KEYBOARD OPERATED SWITCHING UNIT 3 Sheets-Sheet 3 Filed Dec. 28, 1961INVENTORS. ARTHUR M. PASINSKI. RICHARD J. JABLONSKI.

ATTORNEY.

United States Patent 3,085,746 KEYBOARD OPERATED SWITCHING UNlT ArthurM. Pasinski and Richard J. Jablonski, Detro t, Mich, assignors toBurroughs Corporation, Detroit, Mich, a corporation of Michigan FiledDec. 23, 1961, Ser. No. 162,895 Claims. (Q1. 235-145) This inventionrelates generally to business machine keyboards and particularly tokeyboard operated switch devices.

One of the objects of the invention is to provide an improved keyboardoperated electrical switching unit.

Another object of the invention is to provide for the keyboard of acalculating machine, an inexpensively constructed electrical switchingunit in which contact carrying spring fingers of a matrix of pairs ofindividual switches are respectively mounted on opposite sides of anelectric insulating sheet with the switch contact members on the sameside of the sheet.

A further object of the invention is to provide a switching unit of theabove mentioned character in which'conductor strips arranged in spacedparallel relation on one side of an insulation sheet and other spacedparallel conductor strips arranged in spaced parallel relation on theother side of the sheet in crossed relation to the first, each carrylongitudinally spaced spring fingers arranged in pairs on the same sideof the sheet in parallel with the conductor strips on one side of thesheet and overlying the conductor strips on the other side of the sheet.

Other objects of the invention will become apparent from the followingdescription, taken in connection with the accompanying drawings inwhich:

FIG. '1 is a fragmentary side view partly broken away and in section ofa calculating machine keyboard construction embodying features of theinvention;

FIG. 2 is a fragmentary cross sectional view of the keyboard;

FIG. 3 is a fragmentary perspective view;

FIG. 4 is a perspective view of one of the keys;

FIG. 5 is a plan view of a switching unit associated with the keyboard;

FIGS. 6 and 7 are fragmentary perspective views of certain details ofthe electrical switching unit of FIG. 5;

FIG. 8 is a fragmentary sectional View shown partly in side elevation ofa modification of the device of FIGS. 1 to 7;

FIG. 9 is an enlarged sectional view, similar to FIG. 8;

FIG. 10 is a fragmentary perspective view of a key operated electricalswitching device, and

FIG. 11 is a perspective view of one of the keys and its electricalcontact.

Referring to the drawings by characters of reference and first to FIG.1, there is shown a fragment of a business or calculating machineincluding one of the side plates of a supporting frame, a keyboardframework structure, designated generally by the numeral 22, and akeyboard housing 24. The keyboard framework structure 22 is mountedbetween and on the side plates 20 near the top of the keyboard housing.The keyboard framework structure 22 comprises a lower base plate 26, anupper plate 28, and parallel spacer members 30. The plates 26, 28 andspacer members 30 may be rigid-1y se cured together by any suitablemeans, the upper plate 28 being spaced in parallel relation to the lowerplate by the spacers.

Extending downwardly through both the upper and lower keyboard plates 26and 28 are the stems 32 of a plurality of keys which may be amount keysarranged both in columnar and cross rows. Suitable key tops 34, securedto the upper ends respectively of the keystems 32 3,085,746 PatentedApr. 16, 1963 are provided and project upwardly through clearanceapertures in the top of the keyboard housing 24.

A plurality of key locking slide members 36, of which only one is shown,are provided respectively for the columnar rows of keys, the slidemembers being located between the keyboard plates 26 and 28 ontransverse guide rods 37. Each of the locking slide members 36 has aplurality of hooks 38, and the keystems 32 have clearance slots 40respectively to receive the hooks to hold down depressed keys when theslide members 36 are moved rearwardly. A plurality of amount indexingslide members 42, of which only one is shown, are mounted on the sideframe members 20 below the keyboard base plate 26. The indexing slidemembers 42 each have longitudinally spaced upwardly projecting stopabutments 43, one for each of the key stems 32, to limit rearwardmovement of the indexing slides. Each columnar row of keys is providedwith a key restoring spring 45. The above described keyboard is wellknown in the art and therefore has not been herein described in detail,but for a more detail description of the keyboard and its operation inconnection with a calculating machine, reference may be hand to thepatent of Thomas M. Butler, Pat. No. 2,629,- 547, issued February 24,1953.

In accordance with the present invention, a keyboard operated multiplecontrol system is provided for individually controlling multiplecircuits and comprises, in gen eral, an electrical switching device 44,and individual bridging contacts 46 carried by the keys. The electricalswitching device 44 is mounted on and secured to the upper plate 26 ofthe keyboard structure and the bridging contacts 46 may be suitablysecured to the undersides respectively of the key tops 34, electricallyinsulated from the key stems.

The switching device 44 is a unitary structure and includes an electricinsulating base 48, preferably a rectangular sheet of dielectricmaterial which may be secured to and on the upper keyboard plate 28 byrivets or other suitable means. To one side or top or" the sheet 48there is riveted a plurality of metal conductor strips or busses 50which are equally spaced apart in parallel relation and extend crosswiseof the sheet 48 or parallel to the rows of keys. Each of the conductingstrips 50 has, integral therewith, a plurality of transversely extendingspring fingers, designated respectively by the reference characters A1to Ali) respectively, the fingers being equally spaced apartlongitudinally of the strips and arranged with the corresponding fingersin rows parallel with corresponding columnar rows of the keys. Further,the fingers A1 to A10 extend rearwardly and upwardly at the same acuteangle to the sheet 50, and on their free ends, each of the fingers has acontact beneath its respective key carrying bridging contact 46 forengagement thereby. Each of the strips 50 and its spring fingers may beintegrally formiad by stamping them out of suitable resilient sheet metaTo the other side or bottom of the sheet 48 there is attached a secondplurality of spaced apart parallel busses or conducting strips 52 whichextend crosswise of the strips 50 or parallel to the cross rows of keys.Each of the conducting strips 52 has a plurality of spring fingers,designated respectively by the reference characters B1 to B10respectively. The spring fingers of each of the strips 52 are laterallypositioned therefrom such that the fingers extend generallylongitudinally of the strips in aligned spaced relationship therealong.Further, the spring fingers B1 to B10 project through respectiveapertures 54, provided in the insulating sheet 48, to the other or topside of the sheet in substan- .tially parallel relationship to thespring fingers A1 to A10, the spring fingers extending upwardly andrearb wardly to the sheet 48 at the same acute angle of inclination andhaving contacts on the free ends thereof. 'Ihus, pairs of contacts areprovided for cooperating with the key carrying bridging contacts 46,providing a matrix of selectable, manually settable switches. As shownin the drawings, the spring fingers are extended in length so as toreduce bending stresses on the fingers when they are bridged and flexeddownwardly by the key carrying bridging contacts 46, the fingers beingextended such that the free ends thereof overlie the adjacent ones ofthe strips 50 from front to rear of the switch unit. Depression of a keymoves the bridging contact 46 into engagement with its correspondingpair of the spring finger contacts, the downward movement of the keybeing limited so that the spring fingers are not pressed down to theconducting strip, but instead is tensioned just sufficiently to insureand maintain good contact between the switch component contact members.Interposed between the insulating sheet 48 and the upper metal plate 28of the keyboard structure there is an additional sheet 56 of dielectricmaterial to insulate rivets and any other metallic parts on theunderside of sheet 48 from the keyboard structure.

Referring now to FIGS. 8 to 11 inclusive, the modification shown issimilar to the device of FIGS. 1 to 7 and therefore like parts have beendesignated by like reference characters to avoid repetitiousdescription. The modification differs from the previously describeddevice in that the electrical switching unit 44 is located below thebottom plate 26 of the keyboard frame structure and the lower ends ofthe key stems 32. As shown in FIGS. 8 and 9, the switching unit 44 ismounted flat on a support or insulating board 60 which is mountedbetween and on the machine frame side plates 20 in parallel relation tothe inclined keyboard plate 26, the board 60' being suitably mounted bybrackets or other suitable means. The switching unit 44 may be securedto the board 60 with the aid of retainer strips 62 by bolts and nuts 64,or other suitable means. Insulating members 66 are respectively securedto the lower ends of the keystems 32, the insulating members preferablybeing made of a synthetic resin or plastic material and afiixedrespectively to the undersides of the insulating members are bridgingcontact members 68 cooperable on depression of the keys to engage theirrespective pairs of spring finger contact members.

While the keyboard switching device is shown and described inconsiderable detail, it will be understood that many changes andvariations may be made without departing from the spirit and scope ofthe invention.

What is claimed is:

1. An electrical switching unit comprising, a sheet of electricalinsulating material having a matrix of equally spaced holes arranged inlongitudinal and transverse rows, a plurality of conductor stripsattached to one side of said sheet and extending respectively along thelongitudinal rows of holes, a plurality of contact carrying springfingers carried by and electrically connected each of said conductorstrips, said spring fingers extending transversely to said strips withthe free ends in spaced relation to the said one side of said sheet, asecond plurality of conducting strips attached to the other side of saidsheet and extending respectively along the transverse rows of the holes,a plurality of contact carrying spring fingers carried by andelectrically connected to each of said second mentioned plurality ofconducting strips, said second-mentioned spring fingers extending in thesame general direction as said secondmentioned conducting stripslaterally thereto, said second-mentioned spring fingers projectingrespectively through said holes forming parallel pairs respectively withsaid first-mentioned spring fingers on the said one side of said sheetand inclined thereto.

2. An electrical keyboard switch construction for a data entry devicehaving a key bank support and a plurality of keys arranged in spacedrows and columnar banks intersecting said rows, each of said keysincluding a key button and a key stem mounted for reciprocatory movementin said support, said switch construction comprising a plurality of rowsof conducting strips extending in the direction of said key rows andspaced laterally of each other a distance corresponding to the spacingbetween adjacent key rows, each of said strips being of continuousformation between the ends thereof and having a plurality of integrallyformed spring contact fingers projecting laterally and inclined to theplane thereof and spaced apart a distance corresponding to the spacingbetween adjacent ones of said columnar banks of keys, a plurality ofconducting strips extending in the direction of said columnar banks ofkeys transversely of said rows of conducting strips and spaced laterallyof each other a distance corresponding to the spacing between adjacentcolumnar key banks, each of said columnar extending strips being ofcontinuous formation between the ends thereof and having a plurality ofintegrally formed, uniformly spaced spring contact fingers correspondingto the number of key rows, each of said contact fingers of said columnarstrips being aligned with the contact fingers of a different one of saidrow strips, electrical insulating means separating said strips, and anelectrically conducting bridging plate secured to the bottom of each keybutton and electrically insulated from the key stems.

3. An electrical keyboard switch construction for a data entry devicehaving a key bank support and a plurality of geys mounted forreciprocatory movement in said support and arranged in spaced rows andcolumnar banks intersecting said rows, said switch constructioncomprising a plurality of coplanar conducting strips extending in thedirection of said key rows and spaced laterally of one another adistance corresponding to the spacing between adjacent key rows, each ofsaid strips being of continuous formation between the ends thereof andhaving a plurality of integrally formed spring contact fingersprojecting laterally thereof and spaced apart a distance correspondingto the spacing between adjacent ones of said columnar banks of keys,each of, said fingers having a contact carrying free end spaced from theplane of said strips and overhanging the strip of the adjacent rowspaced therefrom, a plurality of coplanar conducting strips extending inthe direction of said columnar banks of keys transversely of said rowsof conducting strips and spaced laterally of one another a distancecorresponding to the spacing between adjacent columnar key banks, eachof said columnar extending strips being of continuous formation betweenthe ends thereof and having a plurality of integrally formed, uniformlyspaced spring contact fingers corresponding to the number of key rowsand extending in the same direction as and parallel to the fingers ofthe row strips, each of said contact fingers of said columnar stripsbeing of substantially the same length as the contact fingers of saidrow strips and having a contact carrying free end spaced from the planeof the strips and aligned with the contact fingers of a different one ofsaid row strips, electrical insulating means separating said strips, andan electrically conducting bridging plate carried by each key andmovable upon depression of a key into sliding contact relation with thecontact fingers of a columnar extending strip and row extending strip tocomplete an electrical circuit therebetween. v

4. An electrical keyboard switch construction for a data entry devicehaving a key bank support and a plurality of keys arranged in spacedrows and columnar banks intersecting said rows, each of said keysincluding a key stem and a key button on the upper end thereof mountedfor reciprocatory movement in said support, said switch constructioncomprising a plurality of rows of conducting strips extending in thedirection of said key rows and spaced laterally of each other a distancecorresponding to the spacing between adjacent key rows, each of saidstrips being of continuous formation between the ends thereof and havinga plurality of integrally formed spring contact fingers projectinglaterally and inclined to the plane thereof and spaced apart a distancecorresponding to the spacing between adjacent ones of said columnarbanks of keys, a plurality of conducting strips extending in thedirection of said columnar banks ofi keys transversely of said rows ofconducting strips and spaced laterally of each other a distancecorresponding to the spacing between adjacent columnar key banks, eachof said columnar extending strips being of continuous formation betweenthe ends thereof and having a plurality of integrally formed, uniformlyspaced spring contact fingers corresponding to the number of key rows,each of said contact fingers of said columnar strips being aligned withthe contact fingers of a different one of said row strips, electricalinsulating means separating said strips, and a conducting bridging platesecured to the lower end of each key stern and electrically insulatedtherefrom.

5. An electrical switching unit comprising, a sheet of electricalinsulating material, a plurality of spaced apart parallel conductingstrips attached flat to one side of said sheet, a second plurality ofspaced apart parallel conducting strips attached flat to the oppositeside of said sheet in crosswise relationship to said first mentionedplurality of conducting strips, first pluralities of spring switchcontact fingers integral respectively with said first mentionedplurality of conducting strips, said spring fingers substantiallyparallel and extending at an acute angle to the said one side of saidsheet, second pluralities of spring switch contact fingers integralrespectively with said second mentioned plurality of conducting strips,said second plurality of fingers extending through said sheet andlaterally positioned in parallel relation to corresponding ones of saidfirst mentioned fingers forming similarly directed pairs of resilientbridgeable contacts on the said one side of said sheet.

References Cited in the file of this patent UNITED STATES PATENTS

1. AN ELECTRICAL SWITCHING UNIT COMPRISING, A SHEET OF ELECTRICAL INSULATING MATERIAL HAVING A MATRIX OF EQUALLY SPACED HOLES ARRANGED IN LONGITUDINAL AND TRANSVERSE ROWS, A PLURALITY OF CONDUCTOR STRIPS ATTACHED TO ONE SIDE OF SAID SHEET AND EXTENDING RESPECTIVELY ALONG THE LONGITUDINAL ROWS OF HOLES, A PLURALITY OF CONTACT CARRYING SPRING FINGERS CARRIED BY AND ELECTRICALLY CONNECTED TO EACH OF SAID CONDUCTOR STRIPS, SAID SPRING FINGERS EXTENDING TRANSVERSELY TO SAID STRIPS WITH THE FREE ENDS IN SPACED RELATION TO THE SAID ONE SIDE OF SAID SHEET, A SECOND PLURALITY OF CONDUCTING STRIPS ATTACHED TO THE OTHER SIDE OF SAID SHEET AND EXTENDING RESPECTIVELY ALONG THE TRANSVERSE ROWS OF THE HOLES, A PLURALITY OF CONTACT CARRYING SPRING FINGERS CARRIED BY AND ELECTRICALLY CONNECTED TO EACH OF SAID SECOND MENTIONED PLURALITY OF CONDUCTING STRIPS, SAID SECOND-MENTIONED SPRING FINGERS EXTENDING IN THE SAME GENERAL DIRECTION AS SAID SECONDMENTIONED CONDUCTING STRIPS LATERALLY THERETO, SAID SECOND-MENTIONED SPRING FINGERS PROJECTING RESPECTIVELY THROUGH SAID HOLES FORMING PARALLEL PAIRS RESPECTIVELY WITH SAID FIRST-MENTIONED SPRING FINGERS ON THE SAID ONE SIDE OF SAID SHEET AND INCLINED THERETO. 